Statistics of the MASIV 5 GHZ VLA Scintillation Survey

reportActive / Technical Report | Accession Number: ADA483314 | Open PDF

Abstract:

We are undertaking a large-scale VLA 5 GHz variability survey of the northern sky searching for rapid intra-day variability. From four epochs of observations spread over a year we find 56 of the flat-spectrum sources showed significant variability on time-scales from hours to days, with many sources varying episodically on only one epoch during the year. We find that the weaker sources show more frequent variability as well as fractionally larger amplitude variability. Fewer sources were detected at high Galactic latitude, demonstrating that inter-stellar scintillation is the principal mechanism responsible for this IDV. We also see a significant dependence on spectral index with the flatter and more inverted sources more frequently exhibiting scintillation.

Author(s):
Jauncey, David ; Lovell, James ; Rickett, Barney ; Macquart, Jean-pierre ; Bignall, Hayley ; Ojha, Roopesh ; Kedziora-chudczer, Lucyna ; Pursimo, Tapio ; Senkbeil, Cliff ; Shabala, Stanislav
Author Organization(s):
NAVAL OBSERVATORY WASHINGTON DC
Descriptive Note:
Conference paper
Supplementary Note:
Presented at the conference entitled "From Planets to Dark Energy: The Modern Radio Universe," held in Manchester, UK, on 1-5 Oct 2007. Published in Proceedings of Science, PoS (MRU) 040, p1-5, 2007. Prepared in collaboration with Australia Telescope National Facility, Epping, Australia; University of Tasmania, Hobart, Australia; University of California, San Diego, CA; and others. The original document contains color images.
Pagination:
0006

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release
Distribution Statement:
Approved For Public Release; Distribution Is Unlimited.

RECORD

Collection: TR
Identifying Numbers
Monitor Series:
NOBS
 Subject Terms
Joint Capability Areas:
JCA_6.3.3_Spectrum Management; JCA_6_Net Centric; JCA_1.2_Force Preparation; JCA_1_Force Support; JCA_1.2.3_Educating; JCA_4.7.2_Installation Services; JCA_4.7_Base and Installations Support; JCA_6.3_Net Management; JCA_8_Building Partnerships
Communities of Interest:
Materials and Manufacturing Processes
Descriptor(s):
*SURVEYS, *SCINTILLATION, *STATISTICS, NORTHERN HEMISPHERE, SPECTRA, GALAXIES, SYMPOSIA
Field(s)/Group(s):
Atmospheric Physics
Keyword(s):
*MASIV(MICRO ARCSECOND SCINTILLATION INDUCED VARIABILITY), IDV(INTRA DAY VARIABILITY)
Report Date:
2007 Oct 01
Creation Date:
2008 Jul 23